Heating and drying apparatus



March 28,1933. w, E. WESTON 1,902,927

HEATING AND DRYING APPARATUS Filed May 12, 1930 3/ l v l ff f INVENToR.I IWI/fam E. Wes/*on A TTORNEY,

Patented Mar. 28, 1933 WILLIAM E. WESTON, F KANSAS CITY, MISSOURIYHEATING AND DRYING APPARATUS Application led May 12,

My invention relates to heating apparatus and more particularly tofurnaces or the like having fire boxes and flues for outlet of productsof combustion in which gases moveat relatively high speed, and throughwhich a considerable amount of the heat units escape unused. y

Heating apparatus of this general character may comprise a battery ofboilers, each mounted in a fire box, and heated by coal supplied from ahopper or bin to the fire box, for example, the coal being automaticallyfed from a hopper to the fire box. Y

When the coal is stored in a bunker or bin exposed to weather it mayreceive and retain considerable moisture and the mass may be frozenwhereby free flow of the coal toward the furnace is prevented, and asupply of coal provided in a bunker or hopper may contain sufficientmoisture to seriously interfere with proper combustion. When the hopperdelivers coal to a pulverizer from which the powdered .coal is blownAinto a flre box, the moist condition of coal is still moreobjectionable, preventing free flow of the larger particles to thepulverizer andinterfering with proper operation of the pulverizer andblower.-

In view of the conditions above described and similarones encountered inanalogous situations, my invention has for its principal objects toemploy the heat of products of combustion for supplemental heating afterthey have performed their normal service in a combustion chamber to heata column of air by said products of combustion and conduct the heatedair to an area to be heated, to employ the suctional effect of gasesmoving from a furnace through a flue for moving a column of air througha heating zone and a o zone to be heated, to employ the heat of afurnace for heating and drying fuel, and to conduct air heated by afurnace intol heating relation with a body of coal forming the fuelsupply for the furnace.

In accomplishing these and other objects of my invention, I haveprovided improved details rof structure, the preferred forms of whichare illustrated in the accompanying drawing, wherein: Y o -`.Figl is avertical section of a furnace 1930. sum1 No. 451,790.

including supports and a fuel supply conduit shown fragmentarily, and myimproved air heating device combined therewith and shown fragmentarily.f

Fig. 2 is a transverse vertical section of55 the furnace illustrating myimproved device including an air conduit extending through the furnaceand through a coal hopper into a smoke breeching of the furnace. 1

Referring in detail to the drawing:

l and 2 designate front and back walls respectively and 3 and 4 the sidewalls forming the housing and support for batteries of boilers 5 anddrums 6, the top of the housing being closed by asmoke run or breechingv7 65 connected 'to a flue 8 leading to a smoke stack (not shown) andhaving inlet openings 9 from the furnace.

10 designates a center' wall ofthe housing forming separate fire boxes11 and 12. `The 70 lfurnace is built on a floor 13 and each're box haslaterally spaced baffles 14 and 15 projecting vertically respectively,from the upper and lower portions of the furnace form-V ing passes 16,17 and 18, the products of 75 combustion passing from the last pass intothe openings of the smoke breeching and thence to the smoke stack.

The batteries of boilers are selected" to represent one type of furnaceto which 4the 80 invention maybe applied. Fuel may be supplied to thefire kbox through a conduitY 19 communicating through a nozzle 20 with apulverizer 21 that receives coal from the chute portion 22 of a hopper23 located adja- 85 cent the furnace, the pulverized coal being blownthrough the conduit by a fan notV shown, actuated by a motor 24 thatalso operates the pulverizing mechanism.

In order to heat the coal in the hopper for evaporating the moisturethat may be carried thereby, I provide an Vair conduit 25 including aportion 26 extending laterally through the combustion chambers in thelast passes thereof and adjacent the ports from the combustion chambers`into the smoke breeching, but preferably beneath the drums, having aninlet 27 from atmosphere and including a portion28 leading tothe hopper,

a portion 29 located in heating relation with 100 to the smoke stackwill have'suctional effecton gases in the conduit and .drawairtherethrough.

The portion 29 of the air-conduit preferably comprises a plurality ofpipe portions arranged for effective transmission of heat from theconduit to the hopper for heating the coal therein, and preferablycomprises 26 a grille-like assembly of pipes having headers32`conne'ctedwith adjacent ends of the conduit portions 28 and 30, thepipes preferably extending through the walls of the hopper into andthrough the hopper whereby coal introduced into the hopper will bevpartly supported by the grille and in contact with' the grille portionof the conduit. The pipe portionsare thus distributed to form anextended area of the conduitin heating relation with the hopper. y Y

yI further preferablyv install a Vnozzle 33 having an upwardly directedoutlet'34: in the air: conduit portion 30 lwhereby a'pressure mediumsuch as steam may be delivered to thehconduit in the direction ofdesired flow of air ffor'promoting flow of air into the inlet end of theconduit and through Vthe conduit toward the stack.

An opening `35 is 'further formed in thev s conduit portion 28 betweenthe furnace and the hopper, and a valve or damper 36 is pivotallymounted on the conduit to normally close the. opening, whereby cold airmay be admitted to the conduit to mingle withv heated air moving fromthe furnace: and temper the same.

In using the invention the air conduit may be located at any desiredpositionv in or adjacent a fire box or flueto receive heat therefrom andpreferably is` located adjacent the outlet from the fire box toward theflue to absorb fromv the products of combustion, heat hat wouldotherwise be wasted into the The conduit is preferably fixed inopeningsprovided therefor in the walls of the furnace and has one end open toatmosphere and portions leading to an area to be heated, the flow of airthrough the conduit being set up and continued by reason of the mountingof the outlet end ofthe conduit in communication with the flue,'wherebythe draft created in the iine'by Voperationfof the furnace willVaccomplish circulation of air through the conduit,

or byA introducing apressure medium into the conduit.

to assure circulation irrespective of extentV of draft in the iiue andfor controlling theV rate of movement of heated air through the Yconduit, v

VThe conduit maybe led to any area or chamber vwhich it isdesired tosupply with heat, for example to a portion of a building or room, suchlas a greenhouse, dwelling, church or school rooml or the like, and thedevice is particularly useful for employing the otherwise wasted heatfrom a battery of b'oilers for heating purposes-andparticularly forvaporizing moisture in coal 4contained in a hopper or bunker.

The heated air will effectually drythecoal and prevent solidificationoflumps intomasses either by adhesion due to moist condition or freezing,and thus'assure free flow of coal from a bunker toward a hopper and froma hopper to a pulverizer.'VV v Should air be passed at an undesirablyhigh temperature into heating relation with a space to be heated, thedamper 36 rmay be manipulated to admit more or lessvcold'air to theconduit, for reducingy the temperature of the column of air movingvtoward the flue, without suspending iiow of said column, thus affordingcloser control of heatthan would be possible vby varying the amount tofheated air that is ypermitted to move through the conduit, andpreventing overheating of theL heated spaceorof walls of theconduitlocated in heating relation -with said space. v

Attention is called to the fact that in the illustrated structure theoutlet of the lheated air conduit communicates with the smoke stack,chimney or breeching at a point higher than the space to beY heated, inorder-toassure circulation of air through the conduit,

WliatI claim and desire to vsecureby Letters Patent is: 1. Incombination with a furnace havingia ue, .and means-including afuel-containing chamber member vfor supplying fuel-to the. furnace, anair conduit located to'receiveheat from the furnace and havingaportionlo,-l cated to transmit heat to said :chamber member and an outlet endextending-intoftheY conduit located to receive heat from the fur-gv naceand having a portion extending through said'cliamb'er and inlet .andoutlet ends communicating respectively with atmosphere and with saidfurnace outlet for supplying airfto and creating suctionl in saidYconduit.

3. In combination with a. furnace liavinga iiuefmeans including` afuelcontaining reservoir for supplying fuel to the furnace, and a conduitlocated in heat-receiving relation with the furnace and having a portionlocated in heating relation with fuel in said reservioir and an outletend extending into said 4. In combination with a furnace having a flueand a bin for containing coal adapted to be fed to the furnace, aconduit having an air inlet from atmosphere extending through thefurnace and having a plurality of portions extending through said binand an outlet end extending into said flue.

5. In combination with a furnace having a flue and a bin for containingcoal adapted to be fed to the furnace, a conduit having an Y inlet fromatmosphere extending through the furnace and having a plurality ofportions extending in said bin and an outlet end extending into saidflue, and means including a nozzle projecting into said conduit foildelivering a pressure medium thereto.

6. Heating and drying apparatus including in combination with a furnacehaving a flue, and achamber member, a conduit having an inlet end opento atmosphere, a portion in heat exchanging relation with the furnace,an intermediate portion for exchanging heat With the chamber member, andan outlet end portion connected with the flue for inducing flow of airinto the conduit responsively to draft in the flue.

In testimony whereof I aiix my signature.

WILLIAM E. WESTON.

